Key takeaway 1 : Some corrections

Stevia was previously lumped with artificial sweetners. It's not. It's a non-caloric sweetener. And apparently, based on available data, it does not disturb the gut microbiome.

However take care, anything sweet even non-caloric wil create an insulin response. In fact, even passing by a bakery can trigger an insulin response through the smell. The body is that smart…

Key takeaway 2 : Metabolism, it's not just about a sexy body

Metabolism is the energy consumption of the entire body. And that includes consuming energy for moving, for repairing tissues, for building tissues and also for brain function. The brain consumes about 70 to 80% of the energy per day.

In other words, having a great metabolism will improve all those functions : building more muscles, thinking more clearly, …

Key takeway 3 : Thyroid hormones : involved in energy consumption & tissue repair/construction

Thyroid hormones will promote energy consumption (fats & sugars) and tissue repair or production. So having a correctly working thyroid will mean generally leaner body, more muscular body, better ability to recover.

Key takeaway 4 : To make thyroid hormone, you need iodine, l-thyrsoine & selenium.

Usually, people will have enough iodine & l-thyrosine. But it may happen that they don't and therefore they will need to supplement.

Selenium, huberman believes most people could be better ingesting a little bit more of selenium. Recommendation varies, between 100 and 200 micrograms per day. Brazil nuts are the heavyweight champion of foods to get Selenium.

Key takeaway 5 : "Clean" diets can have adverse effects

Clean diets so people eating a lot of vegetables, especially the cruciferous might need to increase iodine consumptions. Similarly, people who are more on a carnivore-like diet shall maybe also increase their iodine consumpations.

Key takeaway 6 : Growth hormone and thyroid hormones are very similar

Growth hormone acts in very similar ways to thyroid hormones : promoting bones, ligaments, … growth and repair.

Key takeaway 7 : Don't eat two hours prior to sleep to optimize growth hormone release

Growth hormone is released every night when you go to sleep. And it's released in the early part of sleep during so called slow wave sleep. The other condition to get GH released is to have blood glucose and insulin low. So don't eat within two hours prior to go to sleep.

Key takeaway 8 : Delta waves product growth hormones

Slow wave sleep is actually associated to delta waves. And therefore, if one can get the brain to produce delta waves during the day, one can increase growth hormone production.

Meditation practice can increase delta wave activity. Binaural beats (specific tones played in right and left ears) is potentially possible alough no solide reasearch exists on that according to Huberman.

Key takeaway 9 : 16 minutes of endurance or weight training exercise boosts your growth hormone

Specific duration and intensity of exercise boosts growth hormone. 60 minutes, not much longer.

Longer training bouts increase cortisol and according to Huberman that's why people who overexercise or exercise a lot can lose their menstrual cycle for example. Indeed, high enough levels of cortisol inhibit testosterone and oestrogen pathways.

Key takeaway 10 : Apnea changes hormonal levels

Studies have shown that apnea changes hormonal levels i.e. testosterone and estrogen. Probably because there are testosterone and estrogen receptors in the viscera and the lungs in particular. But the directionality of the chanes is not clear.

The most effective way to avoid apnea is to nose breath, both during the day and during sleep. Nose breathing therefore promotes healthy hormonal levels through healty sleep and healthy sleep patterns.

Key takeaway 11 : Nose breath all the time

Even during exercise, aerobic exercise.

Key takeaway 12 : Viewing sunlight, here we go again

Viewing sunlight is important for sleep, we know that. But it's also important for setting correct hormonal levels. Because getting sunlight patterns correct, getting enough sunlight promotes dopamine production and therefore promotes sex steroids production.

And correct sunlight patterns also involve not getting bright light during the night.

Key takeaway 13 : Increase of testosterone with Exercise … Unclear

Heavy weight training without failure seems to raise testosterone. With failure seems to lower it (probably due to increase in cortisol). High intensity intervals or sprinting seems to raise testosterone. Now high intensity for a long time or longer runs (75mins+) seem to decrease testoserone. Again probably due to cortisol.

But data are scarce. Also, apparnetly performing weight training before endurance increases testosterone while the opposite is true.